1. Field of the Invention
The present invention generally relates to so-called two piece type connector apparatuses that electrically connect two circuit boards, for example, and more particularly, to shield structures of contacts that are electrically connected.
2. Description of the Related Art
Connectors are widely used as apparatuses that electrically connect electronic devices, such as computers, servers, switching equipment, and large computers.
When transmitting electronic signals at a high speed in the electronic apparatuses, there are problems such as crosstalk noise. Especially, in a back plane such as each module of a computer, a logic module and a memory module, for example, and a circuit board used for performing necessary connections among other circuit boards plugged therein at right angles, it is important to positively match transmission characteristics of high-speed electronic signals.
Hence, for connectors used for connections of the back plane, a balanced transmission technique that performs differential signal transmission capable of canceling out noise that might be generated in transmission of high frequency signals is adopted. Additionally, in order to positively reduce crosstalk noise, a coaxial structure that covers, for example, the outsides of a plurality of signal lines with shield members is adopted, and shield terminals and ground terminals are provided between adjacent signal contact points.
A description will be given of an example of such conventional connectors, with reference to FIGS. 1 through 9.
This conventional connector is a so-called two piece type connector used by connecting a pair of connectors and includes a plug connector shown in FIGS. 1 through 3 and a jack connector shown in FIGS. 4 through 7. The two piece type connector (connector apparatus) is used for balanced transmission.
First, a description will be given of the plug connector. FIG. 1 is a perspective view of the plug connector, FIG. 2 is a diagram of the plug connector seen from the direction indicated by xe2x80x9caxe2x80x9d in FIG. 1, and FIG. 3 is a diagram of the plug connector seen from the direction indicated by xe2x80x9cbxe2x80x9d in FIG. 1.
In a plug connector 1, a housing 2 is formed into a shape including a vertical wall 2a and horizontal walls 2b and 2c. The horizontal walls 2b and 2c are provided at opposing up and down sides of the vertical wall 2a so as to interpose the vertical wall 2a therebetween. In addition, a plurality of plug contacts 3 having substantially bar shapes and passing through the vertical wall 2a are arranged in a matrix-like manner when seen from an end face of the vertical wall 2a. Two plug contacts 3 (denoted by reference numerals 3A and 3B in FIG. 3) arranged side-by-side up and down, that is, in the same column, transmit in pairs signals having symmetrical positive and negative waveforms.
Each of the contacts 3 includes contact points 3a and 3b at opposing ends. The contact point 3a is for making contact with and electrically connecting to a contact point of the jack connector, which will be described later. The contact point 3b is for engaging with and electrically connecting to a throughhole in a board (not shown).
Considering the two contact points 3a of a pair of plug contacts 3 (3A and 3B) as one unit, an angle-like (L-shaped at cross section) shield plate 4 is provided for each unit by covering two sides thereof.
Next, a description will be given of the jack connector. FIG. 4 is a perspective view of the jack connector, FIG. 5 is a diagram of the jack connector as seen from the direction indicated by xe2x80x9ccxe2x80x9d in FIG. 4, FIG. 6 is a diagram showing contacts removed from the jack connector in FIG. 5, and FIG. 7 is a diagram of the jack connector seen from the direction indicated by xe2x80x9cdxe2x80x9d in FIG. 4.
In a jack connector 5, a housing 6 is formed into a shape where horizontal walls 6b and 6c are extending from opposing up and down sides of a vertical wall-like main body 6a. 
A jack contact 7 is formed into an angle-like shape and includes contact points 7a and 7b at the opposing ends. The contact point 7a is for making contact with and electrically connecting to the contact point 3a of the plug connector 1 and is formed to be biforked. On the other hand, the contact point 7b is for engaging with and electrically connecting to a throughhole in a board (not shown) and is formed into a press fit-like shape. Four pairs of contacts 7A and 7B having different shapes are arranged in a column direction and integrally molded into a resin part 7c. A plurality of the jack contacts 7 are arranged in a matrix-like manner when seen from an end face of the main body 6a. The jack contacts 7 are used for transmitting signals having symmetrical positive and negative waveforms by pairing two adjacent up and down (in the same column) jack contacts 7 (denoted by reference numerals 7A and 7B in FIG. 7).
Considering the two contact points 7a of a pair of the jack contacts (7A and 7B) as one unit, a shield plate 8 having a tongue-shaped part 8a on one side is provided for each unit. The shield plate 8 is arranged in parallel with the jack contacts 7 in the column direction (vertical direction). Pin parts 8b located on the opposite side of the tongue-shaped parts 8a protrude from a bottom-side end face of the resin part 7c in FIG. 4.
As shown in FIG. 8, the plug connector 1 and the jack connector 5 are in contact with and electrically connected to each other such that the contacts 3a of the plug contacts 3 are supported by the biforked contact points 7a of the jack contacts 7.
As shown in FIG. 9, in a state where the contact points 3a and the contact points 7a are in contact, three sides of a pair of contact parts (one unit) 9 in each of which the contact point 3a and the contact point 7a are in contact are covered with the shield plate 4 and the tongue-shaped part 8a of the shield plate 8. In addition, one side (the lower side in FIG. 9) that is not covered with the shield plates 4 and 8 is shielded by the adjacent shield plate 4 from the downside adjacent pair of the contact parts (one unit) 9 in the column. Hence, each of the pairs of the contact parts (one unit) 9 arranged in a matrix-like manner is shielded by the shield plates 4 and 8 from adjacent pairs of the contact parts (one unit) 9 in each direction of the matrix. Accordingly, crosstalk generated between adjacent pairs of the contact parts (one unit) 9 arranged closely is reduced.
However, in the above-described conventional connector, the angle-shaped shield plate 4 of the plug connector 1 is provided for each pair of the contact parts (one unit) 9. For this reason, the number of components is large, thus resulting in a lot of assembly processes and high assembly cost.
Also, in the conventional connector, because of its structure, the surroundings (four sides) of one pair of the contact parts (one unit) 9 are not always shielded sufficiently.
It is a general object of the present invention to provide an improved and useful connector apparatus in which the above-mentioned problems are eliminated.
It is another and more specific object of the present invention to provide a connector apparatus that can preferably realize a shield structure capable of reducing crosstalk with a small number of components, and thus with a small number of assembly processes, and also with low assembly cost.
In order to achieve the above-mentioned objects, according to one aspect of the present invention, there is provided a connector apparatus that includes: a first connector; and a second connector connected to the first connector, the first connector including: a first connector body; a plurality of first contacts provided in an end face of the first connector body in a matrix-like manner, each of the first contacts having a first contact point; and a plurality of first shield plates provided between adjacent first contact points of the first contacts in a row direction, extending in a column direction of the first contact points of the first contacts, and shielding at least the adjacent first contact points in each row, the second connector including: a second connector body; a plurality of second contacts provided in an end face of the second connector body in a matrix-like manner, each of the second contacts having a second contact point, the second contact points making contact with and being electrically connected to the first contact points; and a plurality of second shield plates provided between adjacent second contact points of the second contacts in a column direction, extending in a row direction of the second contact points of the second contacts and shielding at least the adjacent second contact points in each column, wherein at least one of the first and second shield plates are formed with slits receiving ends of the other one of the first and second shield plates, and the first and second shield plates are configured and arranged to be engaged in a grid pattern by connecting the first and second connectors so that a contact part including the first and second contact points is arranged within one element defined by the grid pattern.
According to the above-mentioned aspect of the present invention, when connecting two circuit boards, for example, it is possible to realize a shield structure capable of preferably reducing crosstalk with a small number of components, thus with a small number of processes and low assembly cost. In addition, for this reason, compared with the case where balanced transmission is performed by using a pair of contacts, it is possible to make mounting density of the contacts of the connector higher.
In the above-described connector apparatus, the two first contact points of a pair of the adjacent first contacts in a row may form a first unit, and the first connector may include the first shield plates each extending in the column direction and shielding the adjacent first units in the column direction, the two second contact points of a pair of the adjacent second contacts in a row may form a second unit, and the second connector may include the second shield plates each extending in the row direction and shielding the adjacent second units in the column direction, and the first and second shield plates may be configured and arranged to be engaged in a grid pattern by connecting the first and second connectors, and two contact parts forming one unit and each including the first and second contact points may be arranged within one element defined by the grid pattern.
Accordingly, since high-speed signals are transmitted by a balanced transmission method, it is possible to preferably reduce crosstalk.
Also, the first and second contact points may fit in to and make contact with each other.
The connector apparatus having the above-described structure is preferable since it is possible to positively establish electrical connection.
In addition, the ends of one of the first and second shield plates may be formed into pin-like shapes, the ends of the other one of the first and second shield plates may be formed into biforked shapes, and both ends may fit in to and engage each other.
The connector apparatus having the above-described structure is preferable since it is possible to more positively connect the first and second shield plates.
Further, one of the first and second connectors may be provided with third contact points in the corresponding one of the first and second contacts, the third contact points protruding from an end face perpendicular to the end face of the corresponding one of the first and second connector bodies, and the other one of the first and second connectors may be provided with fourth contact points in the other one of the first and second contacts, the fourth contact points protruding from an end face parallel to the end face of the other one of the first and second connector bodies.
With the connector apparatus having the above-described structure, it is possible to preferably and electrically connect two circuit boards arranged such that both principal surfaces are perpendicular to each other.
Additionally, the first and second shield plates may be formed to cover the entire first and second contacts each including one of the third and fourth contact points, respectively.
With the connector apparatus having the above-described structure, it is possible to more preferably reduce crosstalk noise.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the following drawings.